slater



2 Sheets-Sheet 1.

(No Model.)

R.L.SLAT-BR. STEAM BOILER PURNAGB.

Patented May 8, A1883.

\o o Y @gf M 0 E @T $1 z @/E N. PETERS. Pham-L'rlhorlphur. W

(No Model.) 8 2 sneets-sheet 2. R. L. SLATER.

STEAM BOILEB PURNAGB. No. 277,361; Patented May 8,1883.

. WQ A a www m m W l, momm WOQGGOOGOOQ Iqwm r 8 8 bib. NOM.. am. w.@onenwmoooocfuQGQOQQGooQQoWW/lQV om J. ,8 oOQOOOMUOOQQOOQOOAUOOOOOOOOOO\ m mm1 f .Lr

W TNEEEEE.

N. PETERS. Pbobutfnl-npher, Wahinghm. D. C.

UNITED. STATES PATENT OFFICE.

RICHARD L. SLATER, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR TO PERKINS H.BAGLEY, OF SAME PLACE.

STEAM-BOILER F'URNAGE.

' SPECIFICATION forming part of Letters Patent No. 277,361, dated May 8,1883.

` vApplication tiled January 4, 1883. (No model.)

To all whom 'it may concern:

Be it known that I, RICHARD L..SLATER, residing at San Francisco, in thecounty of San Francisco and State of California, have invented certainnew and useful'Improvements in Steam-Boiler Furnaces, of which thefollowing is a specification.

My invention relates to improvements in the construction of furnacesadapted for the heating of steam boilers placed above the flame andcombustion -chamber and the objects of my invention are, first, toprovide afurnace with means whereby the draft and degree of heat may begreatly increased and the combustion of the gases and vapors arisingfrom the burning' fuel may be accomplished; second, to provide a meanswhereby thin streams.

of vital heated air may be discharged into the com bustion-chain berabove the bed of bu-rning fuel, and al'so to certain details ofconstruction, which will be more fully described hereinafter. Iattain'these objects by the means illustrated in the accompanyingdrawings, in which- Figure lis a cross-sectional view of a furnaceembodying my improvements. Fig. 2 is a perspective view of one of thegrooved bricks. Fig. 3 represents a modied form of brick. Fig. 4 is alongitudinal section through the tire-box, taken on line X X of Fig. l.

Similar letters are used to designate like parts throughout the severalviews.

A A represent the steam boilers of a double furnace; B B, the sidewalls, and C the bridge-wall, ofthe combustion-chamber. Ihc

front, bridge, and side walls are made hollow, or with a chamber, D,extending throughout their entire length and from below the line ofgrate-bars to any convenient height above them. A series of perforationsor holes, E, are made in the fire'face of the walls, and commnnicatewith the chamber D near the lower edge or base thereof. Near the upperend of the chamber I make one or more series of perforatious, F,whichcommunicate with the tirebox at any convenient height above the bedof coal upon the grate-bars G. At or near the center of thecombustion-chamber, and extending from the front to the bridge-wall, Iereeta partition-wall, H, which extends up to or above the top of thebridge-wall, and thus divides the tire-box into two compartments, and,in furnaces where double boilers are used, causes an equal amount ofheat and flame to pass under each boiler. The wall H is made hollow, asshown in Fig. 1, and its chamber I is provided with apertures J and K atthe top and bottom, which communicate with the combustionchamber aboveand the ash-pit below the gratebars. Near the center of each 6osubdivision of the combustion-chamber I lay upon and boltto thegrate-bars a strip of casting, L, which extends throughout the length ofthe tirebox, and is sufficiently wide to lap the top faces of twoadjacent grate-bars. This casting carries a series of vertical pipes, M,which extend a short distance Within the ashpit, and are sufficientlyhigh to clear the bed of burning fuel. The door N of the lire-box isalso made hollow, or with a chamber, O, having at its base an opening,P, communicating with the outer air, and at the top the openings Q,communicating with theinterior of the rebox. A series of air pipes, R,are passed through the front wall, S, and extend with aslightly-downward curve into the nre-box, as Shown in Fig. 4. Theoor Tof the ash-pit is to be provided with the usual ventilator, and theremay be other ventilators let into the front wall, if found 8o desirable.The air which enters the ash-pit f will be drawn up through and rbetweenthe grate-bars, and will keep the lower portion of the fuel in a steadyblaze. A portion will also enter the pipe M, and will be discharged intothe lire-box above. Another portion will enter the hollow walls, and,after being heated by contact therewith, will be discharged into thecombustion-chamber above the bed of fuel, and by mingling with thegases, vapors, and unburned products of combustion will thereby supplythem with an increased supply of oxygen, and thus insure their almosttotal con# sumption and greatly increase the effectiveness ot' the fuelby supplying av larger per- 95 centage of live air to the burning coal'than has heretofore been done without the aid of a fan-blower. Theopenings inthe doors of the lire-box and the pipes R in the front lwallsupply-air directly from the outside without beloo ing first heated inthe ash-pit, and their main oflce is simply t augment the supply ofvital air.

The bricks Y, which form the courses where the inner air-'openingsappear in the furnace walls or hinges, are made in the form shownthat isto say, upon one side I make three semicircular recesses, Z 5 but theouter recesses may be made on the edge ot the brick, and only onequarterround, as shown at Fig. 3. These recesses are given a taper from theoutside to theinside end, so as Jto-concentrate the currents of airilowing through them. The brick are laid in a course with the recessedface uppermost. The next course is then laid on with the recessed facedownward, and thus by the two halves coming opposite each other atubular aperture is formed.

Having-thus described my invention, what I claim, and desire to secureby Letters Patent, 1s-

In a steam-boiler furnace, the combination of the boilers A A, sidewalls, B B, and bridgewall C, formed with an airchamber,D, extendingfrom the ash-pit to the fire-chamber, and provided with openings E F,the hollow partition-wall H, provided with openings J K, the gratebars GL, air-pipes M R, and the hollow furnace-door N, having openings P Q, asand for the purposes described.

In testimony that I claim the foregoing I have hereunto set my hand andseal.

RICHARD L. SLATER. '[L. s]

Witnesses:

WlLMER BRADFORD, GHAs, E. KELLY.

